Blister (nonthermal), unspecified ankle, sequela

This code signifies a non-burn related blister that has developed on an unspecified ankle, representing a late effect or complication of an earlier injury or condition. It indicates that the blister is no longer an acute problem but rather a residual issue from a previous event.

Use this code when documenting a chronic or residual blister on the ankle that is not due to heat, chemicals, or radiation, and the specific ankle (right or left) is not documented. This is appropriate for follow-up encounters where the blister is a persistent issue stemming from a past injury or condition.

• Ensure the medical record clearly indicates the blister is a sequela and not an acute injury.
• Verify that the blister is explicitly stated as non-thermal and the ankle laterality is unspecified.
• Always look for more specific codes if the ankle laterality (right or left) is documented.